Liquid crystal displays (LCDs) have been widely applied to televisions, cell phones, public information, and so on for display by virtue of merits such as small volume, light weight, low power consumption, low drive voltage, no radiation and so on, and belong to such a display technology that is most widely used at present.
A liquid crystal display includes a color filter substrate and an array substrate as well as a liquid crystal layer interposed between the two substrates. A common electrode and a pixel electrode are respectively provided on the color filter substrate and the array substrate, and a voltage is applied across the pixel electrode and the common electrode when they are in operation, so that an electric field is generated by a voltage difference between the two electrodes. The alignment of liquid crystal molecules in the liquid crystal layer is modified by the electric field, and in turn, transmittance of light through the liquid crystal layer is changed. Thus, the function of displaying images is achieved.